Cross-Domain Action Ambiguity Experiment 001: Structured Support Decomposition in a Fixed 4B Local Language Model

Scientifically closed dataset and technical note for CDAA Experiment 001, a preregistered synthetic partial-observation model-evaluation study comparing a free-form condition (B3) with a structured support/action condition (B4) on a fixed Qwen3-4B-Q4_K_M local model. B3 scored 110/450 and B4 0/450; paired Delta B4-B3=-0.24444444444444446 with preregistered 95% paired-bootstrap CI [-0.2644444444444444, -0.22222222222222227]. The frozen result class is NO_DIRECTIONAL_SUPERIORITY. Post-run failure localization is explicitly exploratory and separated from the primary endpoint.CDAA is DDPD-adjacent successor work, not DDPD scientific evidence.